Edexcel GCSE Computer Science key terms

Adding numbers represented using only the digits 0 and 1, carrying into the next column whenever a column total is 2 or 3.

A searching algorithm that repeatedly compares a target with the middle value of a sorted search range and discards the half that cannot contain the target.

A binary digit, either 0 or 1; the smallest unit of data.

The number of bits used to represent each sound sample.

A digital image represented as a grid of pixels, with each pixel’s colour stored using binary data.

An ordered sequence of bits used to represent data or a program instruction.

A unit of transmission rate meaning one bit transferred each second; abbreviated bps.

An external testing approach in which testers lack internal knowledge and access credentials, simulating an attack from outside the system.

A criminal who attempts to gain unauthorised access to computer systems for harmful purposes, such as stealing data.

A data type with two possible values: True and False.

An expression that evaluates to True or False, such as a comparison or a combination of conditions.

A variable holding True or False to track a condition and help control a program.

Input at or immediately around the limits of an allowed range, used to check how the program handles those limits.

A point set in a debugger where execution pauses so that the programmer can inspect variable values.

A sorting algorithm that repeatedly compares adjacent values and swaps those in the wrong order.

A pre-existing subprogram available directly in a programming language without importing a library module.

A network arrangement in which all devices connect to one shared main cable, with a terminator at each end.

A unit of data consisting of 8 bits.

An instruction that runs a subprogram, supplying any required arguments.

A digit passed into the next higher place-value column during addition. In binary, two units in one column become one unit in the column to its left.

Changing letters in a string to uppercase or lowercase.

Converting a value from one data type to another, such as converting the string "12" to the integer 12.

A single letter, digit, punctuation mark or other symbol. Python represents a character using a string of length one.

A collection of characters, such as letters, digits and punctuation marks, each assigned a distinct binary code.

A value calculated from data and checked at the receiving end to help detect transmission errors.

A component that generates regular pulses to synchronise CPU operations.

A group of instructions treated as one unit, such as the indented instructions inside a Python loop.